1. Field of the Invention
The present invention relates generally to end-plates for linear motion sliders and linear motion sliders for use with the end-plates and, more particularly, to an end-plate for linear motion sliders and a linear motion slider for use with the end-plate, in which first and second support portions, which contact and support the outer surfaces of balls, are provided in the circumferential inner surface of the end-plate, and a space is defined between the outer surfaces of the balls and a junction surface between the first and second support portions, so that the stiffness of the end-plate is increased, and the balls can stably circulate in a slider, thus reducing noise and vibration, and so that the space serves to keep lubricant therein, thereby the balls can more efficiently circulate in the slider.
2. Description of the Related Art
A representative conventional linear motion unit was proposed in Japanese Patent Publication No. 1987-200015.
The conventional linear motion unit includes a guide rail, which has ball guide grooves therein, a block body, bearing blocks, each of which has an end-plate, and which are coupled to the respective opposite ends of the block body, and a plurality of balls, which are interposed between the guide rails and the bearing blocks.
The block body has therein load ball passing holes, no-load ball passing holes and grooves.
The balls are provided in the pipes, which are provided in the no-load ball passing holes and grooves. Grooves, which hold the opposite ends of the pipes, are formed in the end-plates.
Each groove, which is formed in each end-plate, has a ‘U’-shaped cross-section.
Therefore, when the balls move along the groove, each ball comes into point contact with the groove.
Thus, the balls unevenly move along the groove, thereby causing noise and vibration.
Furthermore, the balls cannot rotate smoothly. Accordingly, there is a problem in that the balls strike parts of the end-plates, thus damaging the end-plates.
Meanwhile, in the conventional linear motion unit having the above-mentioned construction, a lubricant injection hole for supplying lubricant is formed in each end-plate.
Due to spatial restrictions, the lubricant injection hole is formed at an eccentric position in the end-plate.
As such, because the lubricant injection hole is formed at the eccentric position, different amounts of lubricant are supplied to each of the grooves, which are disposed at opposite positions in the end-plate.